Aflatoxins are mycotoxins produced by mold, such as Aspergillus flavus and are found in many forms of human foods, such as cereals, grains, and peanut products. Different forms of aflatoxin, including aflatoxin B1, B2, G1, and G2 are known for their toxicity and carcinogenicity. Various studies suggested a link of aflatoxin exposure with an increased occurrence of liver and lung cancer. Aflatoxin B1 (AFB1), the most toxic compound in this series, has been found to be one of the most potent carcinogens occurring naturally and it was classified as Group I human carcinogen by the International Agency for Research on Cancer (IARC) in 1987. Accordingly, the presence of aflatoxins in food has been recognized as a threat to human health. The presence of these mycotoxins in various foods can be caused by direct contamination via grains and grain products or by the presence of mycotoxins and their metabolites in animal tissues, milk and meat caused by animal consumption of contaminated feed. There exist a great number of reports that suggest intoxication of humans by the consumption of aflatoxins contaminated agricultural products. Epidemiological studies have shown that aflatoxins exposure is associated with increased risk of hepatocellular carcinoma, particularly in combination with hepatitis B virus. Also, it has been shown that the potency of aflatoxins increases in individuals with liver conditions such as hepatitis B infection.
Due to their frequent occurrence and their severe toxicity, guidelines and tolerance levels of aflatoxins have been set in several countries. Wheat is susceptible to these fungi infections through its growth, harvest, transport and storage. Iran has set a maximum residue limit of 5 μgKg−1 for AFB1 in wheat for imports. Accordingly, the low tolerance for food contamination by aflatoxins causes serious economic losses.
Improvement in the determination of mycotoxin levels in grains has been an ongoing effort, and current methods include TLC, fluorescence polarization assay, HPLC, radioimmunoassay (RIA), ELISA, and fiber optic based immunoassays. These methods have some drawbacks, for example chromatographic methods require extended cleanup steps and derivatization after extraction in order to get rid of interfering substances, commercially available ELISAs require enzymatic reactions and washing and separation of bound and free label.
The use of spectrofluorimetry analysis is also hampered when testing natural samples such as blood, urine, foods, cereals, grains, and peanut products. The procedure is made difficult by the complexity of matrices which show a great variety of natural fluorescent compounds whose spectra often overlap the analyte signal. This situation therefore demands tedious separation steps to enable determination of the analyte.
With respect to removing the mycotoxins from the grain, current extraction methods for the removal of mycotoxins from foodstuffs, such as grains, predominantly involve the use of organic based liquid compositions, such as methanol/water mixtures and the like. Herein, compositions and methods are presented for the aqueous based extraction and recovery of mycotoxins from foodstuffs. The compositions also show broad affinity for mycotoxins, and therefore remove a wide variety of toxic contaminants simultaneously.